Elevator door or gate operating mechanism



4 Sheets-Sheet 1 c. o. HARMON ELEVATOR DOOR 0R GATE OPERATING MECHANISM I ;us. l

March 7, 1950 Filed May 4, 1948 'INVENTOR. C/arenre 0. Harman y W M nrramvsys March 7, 1950 c. o. HARMON ELEVATOR DOOR OR GATE OPERATING MECHANISM 4 Sheets-Sheet 2 Filed May 4, 1948 T0 PUSH BU TTOIV CONTROLLER II M ' INVENTOR.

6/0/6009 0. Harmon V BY 5W WM ATYOE'NEYS II llll II H II II [III II March 7, 1950 c. o. HARMON ELEVATOR DOOR OR GATE OPERATING MECHANISM 4 Sheets-Sheet 3 Filed May 4, 1948 INVENTOR. C/a'reflre O. Harmon March 7, 1950 c. o. HARMON ELEVATOR DOOR on em: OPERATING MECHANISM 4 Sheets-Sheet 4 Filed May 4, 1948 KR a? kmBI AR mmjomhzou 7 JNVENTOR. 6 /8776? Harmon BY W E/e vafor C'or A TTORp/E Ys Patented Mar. 7, 1950 UN [TED ES ELEVATOR DOOR OR GATE OPERATINGY MECHANISM Clarence Harmon; DQtroit,1Mich'- Application May 4', 1948', SrialNo; 24,933

lflfllaims. (Cl. 187-52) This invention relatesto operating mechanism for elevator doors or gates. It can be used for raising or lowering the doors or-gates offr'eight elevators and it can also-be usedfor: operating the horizcntally sliding doors of other elevators, such as'passenger elevators.

In operating freight elevators it is the customarypractice tohave the'doors or gates operated by a motor or motors'locatedon each floor. Usually there are two" motors, one on each-side of the shaft, which by suitable driving connections, such as sheaves'or sprocketwheels" and cables or chains, raise andiower the doors or gates when these motorsfareenergized by switch mechanism operated on the. elevator.

It is theobject of theipresent inventionjtoelimimate. the necessity of motorsonaeach'floor' toop+ erate the gates:

It is notbroadly new tousea-motor' on the elevator to connect with operating mechanism oneach floorto operate the gates or doorswhenan elevator arrives'at a floor, but so far asknown, none of these arrangements has been successful for theoperation of vertical sliding doorsor'g ates. There are many dilficulties'inherent in making a satisfactory connection between the driving mechanism on the elevator and the driven mechanism on the wall of the buildi'ng. One of these difiiculties 'is'that all elevators sway and attempts to use operating" connection; such as sprocket wheels which arebroughtinto engagement. with a chain, have been unsuccessful because this swaying-makes it impossible to make a. reliable connection. If a driving" connection" is estab li'shed in such mechanism the connectionis a positive one, and'if resistance is-met'in the open ing and "closing of the doors: or gatesthe mechanism will be damagedif theresistance is too great or if a persongets caught between the gates hewill suffer serious'injuryby reason of the positive drive from the motor to. the gates.

It is the object ofthe invention to provide a drive on the elevator which can dependably couple upwith the driven mechanism on each floor and which will obviate the difiicultiesand deficiencies heretofore found in apparatus? of this kind."

Referring to the drawings:

Fig. 1 is an elevation showing elevator doors or gates'operated by amotor on the top of a freight elevator.

Fig; 2 is an enlarged elevational view taken on the line 2--2 of 1.

Fig.- 3 is a plan-view partly in section taken on the line- 3-3 of Fig. 2". i

Fig. 4 is-aliragmentary elevation ofthe driving 2v and driven connections shown in Fig. 3 showing the position of thedrivingelement'slightly different from that shown in Fig. 3 due to the sway of the elevator.

Fig. 5 is an elevational view of a modified form of'the-invention applied to an elevator with a horizontally sliding door;

Fig; 6 is an elevation taken on the lineG-r'i of Fig. 5; I

Fig. '7 is an elevation of anothermodifioation which, however, is *the preferred form of the invention Referring to 1, lis a freight elevator-with the usual vertically-sliding gates 2 and '3. These dooltsrorgatesare'connectedbythe chains 4 and therodsS. Therchains'pass over sprockets El The'doors counterbalance one another.

The driven mechanism for raising "o1" lowering the doors comprises a chain I, a sprocket wheel 8, a pair of spur gears 9 and Ill and a driven fr'ic tion roll I l. The driving mechanism isshown in detail inFig; 2; A large-driving friction roll l2 is-journalled at !3 on :the bracket lton'motorcarrying arm l5; Attached to this arm is a solenoid armature It; Solenoid I! is contained a housing l8 located on the top-19 of the-elevator. The motor'housing is pivoted at it: to this housing. The solenoid housing is and motor housing are supported on abasezl' which can beadjusted alongthe top of the elevator to de termine'the: amount of load or pressure of the driven roll 12 on the driven friction roll H. The further to: the right'that" the base 25 is. adjusted thegreater will'be: the angle of a line through the journal, lS-of thedrivenroll l2 and pivot 2d anda vertical'liner'through' the pivot 2% The grcaterthat angle the greater the moment of the load ofthe driving'mechanisni on the driven mechanism-andthe better the traction. Hence, it is possible to determine by the adjustment of this base the amount of resistance which will causethe rolls to slip. The greater'th'e angle of the driving roll shaft from the vertical line through: the-pivot 2B the greater resistance itwill be able to overcome-before the. driven rolls slip.

As long as the elevator" driving motor is energizedsolenoid ll; isenergized because the circuit fiz'connects through wires 23'to the main motor circuit of the elevator. Hence, when the con troll'er on the elevator is swung to operating position solenoid fl'is energized anddraws the armature 15 in and swings the driving roll 'l 2 away from the-driven roll H;

When" the car arrives at a floor. the operator throws off-the controlswitch whichcontrols the circuit for the elevator motor and also the solenoid. The driving roll drops down on the driven roll, then a push-button switch on the car is closed and the circuit 24 which leads to the motor A is completed. This causes the motor to rotate the driving roll I2 to drive driven roll II which in turn, through the spur gears 9 and Ill, operates the sprocket 8 and the chain 1 which pulls the doors open. There will be a limit switch (not shown) which will break the circuit when the doors reach a fully open position.

When the operator desires to start the car again he must first close the doors by pushing on another button which sends the current in a reverse direction through the motor and causes the motor and the friction wheels to rotate in the opposite direction and thereby cause the chain 1 to move in the opposite direction and close the doors. A limit switch (not shown) will break this circuit when the doors reach closed position. When the doors reach closed position they will reestablish the circuit to the elevator motor (not shown) which has been broken when the doors or gates begin to open. This is the common arrangement.

Figs. 5 and 6 show my invention used in connection with a horizontally sliding door or doors. Here in Fig. 5 only one driving mechanism is shown for operating one door 26. A chain 21 is fastened to the top of the door at 28. The door has rollers 29 which travel on track 30. Chain 21 is driven by sprocket 31 which is on end of shaft 32. A pair of bevel gears 33 are used to couple shafts 32 and 34 in driving relation. Shaft 34 is driven by gear 35 in mesh with gear 36 on the driven roll shaft. The driven roll II is driven by the large driving roll l2. The driving mechanism is exactly the same as already described and no further description is necessary.

Referring to Figs. 3 and 4, it will be seen that the driven roll is a rubber roll while the driving roll is a steel roll. The drive is entirely by friction. If the load to be moved is too great the rolls will slip instead of drive. usually takes somewhere from 30 to pounds to move the vertically moving elevator gates or doors. These gates are counter-balanced one against the other. All the power that is required to move the gates is what is necessary to overcome the friction in the guides and actuating mechanism. There is considerable gear reduction from the motor through the large driven gear 31 and the small motor-operated driving gear 38, through the spur gears 9 and Ill and the chain sprocket 8. The angle that the driving roll shaft is to a vertical line through the pivot on which the motor housing (the roll-carrying arm) swings determines the amount of traction of the two friction rolls. As already explained, the greater the angle the greater the amount of the load of the driving roll, the motor-carrying arm l5 and the motor A, and hence the greater pressure between the two rolls. The unit carrying the motor and the driving roll can be adjusted along the top of the elevator to get such a moment or load of the driving roll pressing on the driven roll as to make sure that the rolls have a sufficient traction to operate the doors under all normal conditions. But preferably the margin of friction or the traction will be sufficient only to insure such operation with no abnormal resistance. If the load on the mechanism becomes too great by reason of some obstruction against the doors or a person getting For instance, it b caught between the doors, then with this small margin of traction slippage will take place. Hence with any obstruction the door mechanism will stop driving and therefore save the operating mechanism from serious injury or save a person or some other object from serious harm.

Another feature of the improvement is shown in Figs. 3 and 4. Note how the places of contact between the driving and driven roll may change. The driven roll can be made, say six inches or more long. This allows a considerable surface lengthwise along the roll in which the driving roll 12 may contact. In Fig. 3 the contact is almost in the middle of both rolls. In Fig. 4 the contact is not in a full contact and is out at the end of the driven roll. This is a desirable feature for it insures the contact and the rolls coming together in driving relation when the larger roll is dropped onto the smaller roll. This is not possible where it is proposed to drop onto the driving chain for the doors a sprocket wheel mounted on the elevator. As there is considerable sway in most elevators, hence the sprocket wheel may or may not catch in the chain so apparatus of this kind cannot be depended upon for satisfactory operation. Of course, other forms of friction drive could be used so when driving and driven rolls are recited in the claims it should. be understood that these other equivalent friction drives are covered.

Another feature of my apparatus is the effort required to move the elevator doors on different floors may vary. It is, therefore, possible on different floors to use a different gear reduction between the driven roll and the lifting chain to provide about the same safety-margin of driving effort over operating load. By driving effort is meant the maximum traction before slippage of the rolls which provides the safety factor which is believed to be new in a door actuating con.- nection between mechanism on the elevator and mechanism located on the wall of the building.

The preferred form of the invention is shown in Fig. 7. Here the arm or motor housing 39 has its center of gravity to the right of shaft 40 so that the driving wheel I2 is normally maintained out of contact with the driven roll II which drives sprocket 8 and chain 1. A torque motor B has a reduction gearing connection 42 with pulley wheel 43. This pulley wheel 43 has two grooves, one in which the chain 44 rests and in the other the chain 45. Chain 44 is connected to the retiring cam which releases the door interlock (not shown). The other chain 45 is connected to lever arm 46 which is connected by shaft 40 with the motor-carrying arm 39. This lever arm is counterweighted by counterwei hts 41 and its range of movement is controlled by set screws 48 and 49.

The amount of pressure of the driving roll upon the driven roll may be varied bv altering the torque of the torque motor. This can be done by introducing different amount of resistance into the torque motor circuit by wellknown resistance inserts. This torque and pressure will determine the margin of tractive effort over normal load.

The operation is as follows: When the elevator is at rest at a floor, the torque motor can be energized through the circuit 52 by a push button (indicated in Fig. 7) in the car. This will energize the circuit 50 leading to the torque motor B provided, however, the car is at rest at a floor, and the automatic switching mechanism (not shown) 4 in the controller has closed the circuit through e the controller. The same circuits and push button furnish current to circuit 53 leading to motor A to drive the driving roll l2, which in turn drives the driven roll ll, and causes the movement of the chain 7 to operate the vertically sliding doors, as has already been described in connection with Fig. 1. However, as stated below, circuit Ed has to be closed before circuit 53 to motor i5 is closed. When the doors close a limit switch (not shown) will automatically discontinue the motor energization and also close the switch to the elevator motor so that the elevator may be made to move up or down by operation of the controller on the elevator.

When the push button switch in the car is released or the limit switch opens the circuit 53, the circuit 58 to the torque motor Bis also broken and the driving motor A and the driving roll is returned to the idle vertical position by gravity. Hence, the driven mechanism is out of contact with the driven roll and there will be no abrasion of the rubber driving roll by reason of the swaying of the elevator. In this respect this torque motor arrangement is an improvement over the gravity driving arrangement used in the other modification of the invention, shown in Figs. 1, 2, 5 and 6, because in this modification (Figs. 1, 2, 5 and 6) the driving rolls are in contact at all times while the car is at rest and the solenoid circuit is de-energized. This arrangement of Fig.

'7 requires less current as the current is only on when the doors are being closed or opened.

As stated above, circuit 5 has to be closed before the push button will be efiective to energize lil circuit 53 to the motor A. This circuit 5 t leads to the retiring cam that controls the elevator door interlock. This door interlock has to be released before the driving motor A can be energized.

We have not attempted to show these circuits and switches in detail as such circuits are well known in the elevator art and they are no part of my invention.

I claim:

1. Actuating mechanism for the gates or door guarding the opening into an elevator shaft at each floor of a building, having in combination a driving unit on the elevator having a friction driving roll supported on a pivoted arm which in turn is supported on a base adjustable laterally of the elevator to change the angle of the arm to the vertical and hence moment of the driving roll at the limit of the downward movement of the arm, a driven friction roll for location on the building and on which the driving roll rests when the arm is dropped in tractive but slipping relation under an overload, driven operating connections for location on the building and for the elevator door or doors coupled with the driven friction roll, and means for keeping the arm raised except when it is desired to drop the driving roll on the driven roll preparatory to operating the door or doors.

2. The combination claimed in claim 9 in which the driven operating connections include reduction gearing in which the gear ratio may be varied d to meet the load furnished by the door or doors on each floor.

3. The combination claimed in claim 9 in which the friction rolls have suificient width to vary the contact zone between. the rolls and allow for swaying of the elevator.

4. The combination claimed in claim 9 in which one or more of the friction rolls has a periphery of material with a high coefiicient of friction, such as rubber.

5. The combination claimed in claim 9 in which the means for keeping the arm raised is a solenoid.

6. The combination claimed in claim 9 in which the means for keeping the rolls disengaged is gravity and the means for bringing the driving roll into contact with the driven roll is a torque motor.

7. The combination claimed in claim 9 in which the means for bringing the driving roll into contact with the driven roll is a torque motor.

8. The combination claimed in claim 9 in which the means for bringing the driving roll into ongagement with the driven roll is a torque motor with a circuit in which a variable resistable element may be inserted to vary the margin of tractive effort over the normal load.

9. Actuating mechanism for the gates or doors guarding the opening into the elevator shaft at each floor of a building, having in combination a motor operated driving unit on the elevator having a movable member journalling a friction driving roll, said journalling member arranged to be normally positioned to have the driving roll out of driving position, a base for supporting the said journalling member movably on the elevator, a driven roll for journalling on the building at or adjacent the elevator shaft, transmission connections for location between the friction driven roll and the gate on the building for moving the gate in opposite directions with the rotation of the driven roll, electrically controlled means for bringing the driving roll into friction driving contact with the driven roll, and power means for rotating the driving roll to thereby counter rotate the driven roll and thereby cause the transmission connections to open or close the gate.

10. The combination claimed in claim 9 in which the means for bringing the driving roll into contact with the driven roll is a torque motor, a pulley wheel and draft members which both go over the pull wheel, one to release the latch on the gates and the other to move the journalling member to bring the drive and driven roll into frictional driving contact.

CLARENCE O. HARMON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

